Camera

ABSTRACT

A camera having a transport device for stepwise transport of a film in each case by the length of a respective picture, wherein the transport device includes a film take-up shaft which is driven by way of a winding reel on which a pull element, preferably a cord, is wound, on which film take-up shaft the film can be wound from a film supply spool, in particular from an inserted film cartridge, wherein the free end of the pull element (2) projects into the open through an opening in the housing (17) of the camera and the film (14) is transported stepwise by the length of a picture by pulling on the pull element (2), wherein the winding reel (8) is adapted for automatically winding on the pull element (2) after transport of the film (14) by the length of a picture.

[0001] The invention concerns a camera having a transport device forstepwise transport of a film in each case by the length of a respectivepicture, wherein the transport device includes a film take-up shaftwhich is driven by way of a winding reel on which a pull element,preferably a cord, is wound, on which film take-up shaft the film can bewound from a film supply spool, in particular from an inserted filmcartridge.

[0002] In photographic cameras it is usual for the film strip which isrolled up in a condition of being protected from light in filmcartridges to be transported with a stepwise movement out of the filmcartridge past an exposure window onto a film take-up shaft. In theknown cameras transportation of the film is usually effected by manualactuation of a winding wheel or a winding lever or by means of anelectric motor.

[0003] Thus, U.S. Pat. No. 3,426,663 discloses an endoscope camera inwhich transportation of the film is effected by way of a bottom cablearrangement including an actuating lever. It is also known from U.S.Pat. No. 4, 164,333 in relation to an endoscope camera for the film tobe advanced by means of a pull element which passes outwardly along anendoscope, wherein the free end of the pull element is connected to awinding wheel mounted on the endoscope so that transportation of thefilm is effected by a rotary movement at that winding wheel. Both U.S.Pat. No. 3,866,602 and U.S. Pat. No. 4,038,977 describe transportdevices in endoscope cameras in which the film is transported with astepwise movement.

[0004] The object of the invention is to provide a novel camera whichhas a transport mechanism which is simple to operate.

[0005] In accordance with the invention that is attained in that thefree end of the pull element projects into the open through an openingin the housing of the camera and the film is transported stepwise by thelength of a picture by pulling on the pull element, wherein the windingreel is adapted for automatically winding on the pull element aftertransport of the film by the length of a picture.

[0006] In a camera of such a design configuration therefore, between theindividual exposures, film transport is effected over the length of apicture by pulling on a pull element, for example a cord. In thatrespect, the term length of a picture is used to denote the film advancebetween two exposures, namely the sum of the length of the exposednegative (for example 36 mm) and the usual intermediate space betweenthe exposed negatives.

[0007] German patent specification DE 195 22 742 admittedly discloses aphotographic camera in which, prior to exposure of the film strip, theentire film strip is wound onto the film winding-on spool in one pullfrom the film cartridge by pulling on a cord which is wound on a drumconnected to the film winding-on reel, and the cord is removed from thecamera after the winding-on operation has been effected. That camerahowever does not involve stepwise transport of the film by way of a cordbetween the exposures. That is effected in that case—as is usual—by wayof a hand wheel.

[0008] The camera according to the invention is preferably in the formof a disposable camera which is already fitted with a photographic filmby the camera manufacturer and which, after exposure thereof, togetherwith the film strip, is sent to a developing laboratory for developmentof the film. As the cord is wound onto the winding reel again after eachfilm winding-on operation, the length of the cord does not need tocorrespond to the length of a film—a 24×36 mm film is about 90 cm long.It is sufficient if the cord is of such a length that it can transportthe film by the length of a picture, for example 36 mm plus the spacingbetween negatives.

[0009] In order to make handling of the camera according to theinvention as simple as possible for the user, a further advantageousembodiment of the invention can provide that a holding element, forexample a ring, is arranged at the free end of the cord.

[0010] Further advantages and details of the invention will be describedin greater detail with reference to the specific descriptionhereinafter. In the drawing:

[0011]FIG. 1 is a front view in functionally diagrammatic form of thesubject of the invention,

[0012]FIG. 2 is a perspective view of the device for transporting a filmstrip of the invention,

[0013]FIG. 3 shows a view on an enlarged scale of the part indicated atA in FIG. 2, and

[0014]FIG. 4 shows an exploded view of a further embodiment.

[0015]FIG. 1 diagrammatically shows a front view of the camera 1according to the invention, on the housing 17 of which is arranged awinding knob 5, beside the lens 4. The winding knob 5 serves to rewindthe film strip which, after exposure, has been completely wound onto thefilm take-up shaft. Projecting laterally out of the housing 17 is thefree end of a cord 2 which serves as a pull element and on which ismounted a holding element 3 in the form of a ring to provide for betterhandling. The opening (not shown) out of which the cord 2 which can bemade from the most widely varying flexible materials such as for exampleplastic material or natural fiber projects into the open is desirablylight-tightly closed by suitable means. If the camera is a disposablecamera, the operation of rewinding the film which has been wound ontothe film take-up shaft can also be effected in the dark room of adeveloping laboratory so that the provision of a winding knob on thehousing is not absolutely necessary. A further possible way of rewindingthe film is described in greater detail hereinafter.

[0016] In the case of the device shown in FIGS. 2 and 3 for the stepwisetransport of a film strip 14 from a film supply spool 16 onto a filmtake-up shaft 6, the cord 2, at the free end of which is arranged aholding element 3, is wound with its other end onto a winding reel 8.The winding reel 8 at which a return spring 9 is arranged drives thedrive wheel 7. The drive wheel 7 in turn engages into the gear 16 whichis non-rotatably connected to the film take-up shaft 6 so that, when thewinding reel 8 is rotated by pulling on the cord 2, the film take-upshaft 6 is caused to rotate by way of the drive wheel 7 and in that waythe film 14 is wound onto the winding shaft 6. A locking lever 10additionally engages into the drive wheel 7, wherein the locking lever10 is connected to the counting wheel 13 by way of an eccentric shaft11.

[0017] The mode of operation of the camera according to the inventionwill now be described with reference to the portion A shown in FIG. 3.By pulling on the cord 2, the winding reel 8 is caused to perform arotary movement. The drive wheel 7 is also caused to rotate by way ofthe freewheel entrainment means (not shown) mounted on the winding reel8. The drive wheel 7 subsequently drives the film take-up shaft 6 by wayof the gear 16. In that way film 14 is pulled out of the film supplyspool 18 and entrains the counting wheel 13 which engages intoperforations 15 in the film 14. After a full revolution of the countingwheel 13, which precisely corresponds to the length of a picture, thedrive wheel 7 is blocked by way of an eccentric shaft 11 with an opening11 a and a locking lever 10. When the cord 2 is released, the cord isretracted into the camera housing 17 by virtue of the return spring 9which is tensioned on the winding reel 8, and the cord is wound onto thewinding reel 8 again. After exposure has taken place, by again pullingon the cord, the film can be transported by a further picture.

[0018] The exploded view shown in FIG. 4 illustrates another embodimentof a camera according to the invention. In the assembled condition theillustrated parts are fixed substantially in or on the main body 19 ofplastic material. The film cartridge 18 is disposed in the receivingmeans 19 a while the film take-up shaft 6 is arranged in the oppositelydisposed part 19 b. The take-up shaft 6 is driven by an internal shaft 6a by the gear 16, wherein the film passes behind the aperture with thelens 4, as is generally usual in cameras. What is novel is the drive forthe gear 16 and therewith the film take-up shaft 6. More specificallythis is not effected as in the state of the art by means of a windinglever, by directly driving the gear 16 with the thumb or by motor means,but by way of a special cable pull mechanism.

[0019] The cable pull mechanism includes a winding reel 8, on which iswound a cable 2 with a ring 3 fixed at the end. The winding reel 8 isspring-loaded by a return spring 9 which, after release of the cord 2which has been pulled out, winds it onto the winding shaft again. Thewinding shaft, by way of the coupling gear 27 and the freewheel 28,drives the gear 7 which in the installed condition is in engagement withthe gear 16. The freewheel has resilient toothed arms which engage intoan internal tooth configuration in the drive wheel 7, more specificallyonly in the direction in which the cord 2 is pulled out. When the cord 2moves in (being wound on the winding reel 8 by the return spring 9) thefreewheel 28 rotates freely with respect to the drive wheel 7.

[0020] So that picture transport is effected in each case only by adesired amount when a pulling force is applied to the cord 2, the devicehas a locking lever 10 which, in this embodiment, engages into the teethof the coupling wheel 27 as soon as the film has been transported by thefull length of a picture. After exposure has taken place that lever 10is released again, in which case the shutter release 29 or a membersecured thereto pivots the lever 10 out of the groove 11 a in the member11, in a manner not shown herein.

[0021] The lever 10 is controlled by way of the lever 30 which movesalong the eccentric member 32 and is connected to the locking lever 10by way of a locking lever spring 31. The disk 11 and the eccentricmember 32 are driven by the “counting wheel” 13 which engages into theperforations 15 in the film. Overall therefore the last-describedcomponents represent a device for detecting the film advance movement.When the film advance movement has taken place to such an extent thatthe counting wheel 13 and therewith the members 11 and 32 have rotatedthrough precisely one revolution, winding-on is blocked by way of thelever 30, the locking lever spring 31 and the locking lever 10, untilthe next exposure is effected by actuating the shutter release. Asalready mentioned, the shutter release releases the locking lever andtherewith the winding-on mechanism.

[0022] The counting wheel 13, by way of a freewheel 20, also drives theshutter mechanism which is described hereinafter. The shutter mechanismincludes a connecting wheel 21, by way of which a stressing spring 22for the shutter is driven. The spring 22 acts on the shutter wheel 23which is initially blocked. By actuation of the shutter release, theshutter wheel 23 is released in a manner not shown in detail herein androtates rapidly under the force of the spring 22. That movement istransmitted by way of the shutter lever 24 to the actual shutter 26which thus briefly opens the aperture 25 a in the shutter plate 25.Overall therefore pulling on the cord not only implements filmtransportation but also, indirectly by way of the counting wheel,stressing of the shutter.

[0023] If the invention has been described by reference to this specificembodiment by way of example, It will be appreciated that modificationsand means which are suitable for carrying the concept of the inventioninto effect can certainly be envisaged and are within the scope of theinvention. Thus for example the winding reel could be arranged directlyon the film take-up shaft. It would equally be possible to lock thefreewheel of the spring-loaded winding reel and thus to provide that thefilm is rewound from the film take-up shaft into the film supply spoolby way of the return spring.

1. A camera having a transport device for stepwise transport of a filmin each case by the length of a respective picture, wherein thetransport device includes a film take-up shaft which is driven by way ofa winding reel on which a pull element, preferably a cord, is wound, onwhich film take-up shaft the film can be wound from a film supply spool,in particular from an inserted film cartridge, characterized in that thefree end of the pull element (2) projects into the open through anopening in the housing (17) of the camera and the film (14) istransported stepwise by the length of a picture by pulling on the pullelement (2), wherein the winding reel (8) is adapted for automaticallywinding on the pull element (2) after transport of the film (14) by thelength of a picture.
 2. A camera as set forth in claim 1 characterizedin that the winding reel (8) drives the film take-up shaft without astep-up transmission means or by way of a transmission including gears(7, 16) and/or a slipping clutch.
 3. A camera as set forth in claim 2characterized in that the winding reel (8) drives a—preferably coaxiallyarranged—drive gear (7) which is in engagement with a—preferablylarger—gear (16) which is non-rotatably connected to the film take-upshaft (6).
 4. A camera as set forth in one of claims 1 through 3characterized by a device (11, 13, 30, 31, 32) for detecting the filmtransport distance and a locking means (10) of the film transportdevice, which is controlled in dependence on said detection device (11,13, 30, 31, 32) and which locks the film transport until the nextexposure as soon as the film transport distance precisely corresponds tothe length of a picture.
 5. A camera as set forth in claim 4characterized in that the device (11, 13, 30, 31, 32) for detecting thefilm transport distance actuates a counting wheel (13) engaging into thefilm perforations and an eccentric shaft (11, 32) or the like which isdriven thereby and which actuates a locking lever (10).
 6. A camera asset forth in claim 5 characterized in that the locking lever (10)engages the film take-up shaft (6), a member (16) non-rotatablyconnected thereto or the transmission means (7, 16) between the filmtake-up shaft (6) and the winding reel (8), in particular the drive gear(7).
 7. A camera as set forth in one of claims 1 through 6 characterizedin that the winding reel (8) is spring-loaded by a return spring (9). 8.A camera as set forth in one of claims 1 through 7 characterized in thatthe winding reel (8) is connected to the film take-up shaft or the drivewheel (7) in freewheeling relationship in the direction opposite to thepulling direction of the pull element (2).
 9. A camera as set forth inone of claims 1 through 8 characterized in that a holding element (3),for example a ring, is arranged at the free end of the pull element (2).10. A camera as set forth in one of claims 1 through 9 characterized byan optical display means for displaying the conclusion of film transportby the length of a picture after pulling on the pull element.
 11. Acamera as set forth in one of claims 1 through 10 characterized in thatthe winding reel which is rotated by pulling on the pull elementdirectly or indirectly stresses a spring-loaded shutter device (20, 21,22, 23, 24) for actuating a shutter (26) closing at least one aperture(25 a), which after actuation of a shutter release (29) briefly opensthe aperture(s) (25 a) for film exposure.
 12. A camera as set forth inclaim 11 characterized in that the film (14) which is transported by thewinding reel over the film take-up shaft (6) drives a gear (13) which isin engagement with the film perforations and which stresses thespring-loaded shutter device.
 13. A camera as set forth in one of claims1 through 12 characterized in that it is a disposable camera.
 14. Amethod of transporting a film in a camera as set forth in one of claims1 through 13 characterized in that by pulling on the pull element thewinding reel is rotated and at the same time the return spring thereofis stressed and the film is moved by the length of a picture and woundonto the film take-up shaft drivingly connected to the winding reel andwhen the pull element is released the spring-loaded winding reel returnsto the starting position and in that case the pull element is wound ontothe winding reel again.